Scippy

SCIP

Solving Constraint Integer Programs

heur_randrounding.h
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1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
6 /* Copyright 2002-2022 Zuse Institute Berlin */
7 /* */
8 /* Licensed under the Apache License, Version 2.0 (the "License"); */
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23 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24 
25 /**@file heur_randrounding.h
26  * @ingroup PRIMALHEURISTICS
27  * @brief randomized LP rounding heuristic which also generates conflicts via an auxiliary probing tree
28  * @author Gregor Hendel
29  *
30  * Randomized LP rounding uses a random variable from a uniform distribution
31  * over [0,1] to determine whether the fractional LP value x should be rounded
32  * up with probability x - floor(x) or down with probability ceil(x) - x.
33  *
34  * This implementation uses domain propagation techniques to tighten the variable domains after every
35  * rounding step.
36  *
37  * @see: The most relevant publication is Raghavan & Thompson,
38  * "Randomized rounding: A technique for provably good algorithms and algorithmic proofs",
39  * Combinatorica 7 (4): 365–374
40  * 1987
41  */
42 
43 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
44 
45 #ifndef __SCIP_HEUR_RANDROUNDING_H__
46 #define __SCIP_HEUR_RANDROUNDING_H__
47 
48 #include "scip/def.h"
49 #include "scip/type_retcode.h"
50 #include "scip/type_scip.h"
51 
52 #ifdef __cplusplus
53 extern "C" {
54 #endif
55 
56 /** creates the rand rounding heuristic and includes it in SCIP
57  *
58  * @ingroup PrimalHeuristicIncludes
59  */
60 SCIP_EXPORT
62  SCIP* scip /**< SCIP data structure */
63  );
64 
65 #ifdef __cplusplus
66 }
67 #endif
68 
69 #endif
SCIP_RETCODE SCIPincludeHeurRandrounding(SCIP *scip)
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
type definitions for return codes for SCIP methods
type definitions for SCIP&#39;s main datastructure
common defines and data types used in all packages of SCIP